1. Field of the Invention
The present invention is a radially self-expanding stent and stent-graft for treating bifurcated and other branched vessels of a patient, and methods for manufacturing and implanting the stent and stent-graft.
2. Description of the Related Art
Medical prostheses frequently referred to as stents and stent-grafts are well known and; commercially available. These devices are used within body vessels of humans and other animals for a variety, of medical applications. Stents and stent-grafts are, for example, used to repair (i.e., treat) abdominal aortic aneurysms. An abdominal aortic aneurysm is an enlarged (i.e., dilated) and weakened diseased area of the portion of the aorta between the renal artery branch (i.e., the location at which the renal arteries meet the aorta) and the iliac bifurcation (i.e., the location downstream from the renal artery, branch at which the aorta branches or divides into the iliac arteries). Stenosis, a narrowing and occlusion of the aorta typically caused by tissue buildup, also is often present at these aneurysms. Aneurysms and stenosis at the carotid artery bifurcation (i.e., the location at which the common carotid artery branches into the internal carotid artery and the external carotid artery) are also treated with stents and stent-grafts.
The Parodi U.S. Pat. No. 5,591,229 is directed to an aortic graft for repairing an abdominal aortic aneurysm. Briefly, the graft includes an elongated tube having first and second ends, and securing means for securing the first end of the tube to the aorta. The securing means is an expandable thin-walled member with a plurality of slots parallel to the longitudinal axis of the member. The thin-walled member is configured for delivery in an unexpanded and undeformed diameter state with an inflatable balloon within the member. After being intraluminally delivered to the site of the aneurysm, the balloon is inflated to radially extend the thin-walled member to an expanded and deformed diameter state. The first end of the thin-walled member is thereby secured to the aorta. Deflation of the balloon causes it to be disengaged from the thin-walled member and permits its withdrawal.
A graft for treating an aneurysm which extends above the renal arteries is shown in FIG. 7 of the Parodi patent. This graft includes a thin-walled securing member which is interconnected to the tube by at least one flexible connector member. The flexible connector member spans the part of the aorta adjacent the renal arteries so that blood flow through the renal arteries is not obstructed. There remains, however, a continuing need for stents and stent-grafts for treating branched vessels. Improved stents and stent-grafts for treating abdominal aortic aneurysms and/or stenosis at the carotid artery bifurcation would be especially useful. For example, stents and stent-grafts capable of remaining fixed vessel as the diseased area of the vessel expands would be desirable. Since accurately positioning a stent and stent-graft in a branched vessel can be challenging, a device of this type that can be relatively easily repositioned would also be desirable. In general, stents and stent-grafts having different characteristics enable medical personnel to select a device most suitable for the treatment of the particular indication of the patient.